Troubleshoot Tips - 30 Gal Oilless Unit
The unit is running but no air is showing on the gauge, and there is no air in the tank.
Turn unit off and unplug power cord. Remove the cover from the Pump/Motor assembly to check the transfer tubing connections from the pump to the tank. Sometimes in shipping the Transfer Tube can vibrate enough to work its way out of the connector on the tank and needs to be tapped back in. You can tap it with a rubber mallet or try to reinsert it by pressing by hand.
There is pressure in the tank, which shows on the gauge, but no air will come out of the hose connection.
Check the regulator valve first, turn the knob clockwise to increase the pressure and counter clockwise to decrease the line pressure.
If the air will not register on the output gauge, even after making the adjustments, it is possible that there could be an obstruction inside of the manifold that cannot be cleared by the customer. Refer to a servicing dealer for repair/replacement of the manifold.
The compressor will pump to full pressure, but when it attempts to restart, the motor hums.
Ask if the customer is using an extension cord on the unit. If any extension cords longer the 25 ft. are not heavy enough (12 AWG) there can be enough of a voltage drop that can cause the motor to over heat. The humming is caused by the motor trying to start, but is starving for power because of the low voltage caused by the voltage drop of the extension cords.
In commercial applications as the motor ages, the motor will get harder to start. If this happens, the pump/motor assembly will have to be replaced.
Make sure to use a 20 amp circuit and buy extra air hose if needed to reach jobs. Not extension cords.